func (n *Node) cache(counts ints_int.MultiMap, m ints_ints.MultiMap, key []int32, nodes []lattice.Node) error {
for _, node := range nodes {
err := m.Add(key, setToInt32s(node.(*Node).pat.Items))
if err != nil {
return err
}
}
return counts.Add(key, int32(len(nodes)))
}
func (n *Node) kids(counts ints_int.MultiMap, kids ints_ints.MultiMap, candidates func() map[int32][]int32) ([]lattice.Node, error) {
if n.pat.Items.Size() == 0 {
return n.dt.FrequentItems, nil
}
if n.pat.Items.Size() >= n.dt.MaxItems {
return []lattice.Node{}, nil
}
i := setToInt32s(n.pat.Items)
if has, err := counts.Has(i); err != nil {
return nil, err
} else if has {
return n.cached(kids, i)
}
exts := candidates()
nodes, err := n.nodesFromCandidateKids(exts)
if err != nil {
return nil, err
}
err = n.cache(counts, kids, i, nodes)
if err != nil {
return nil, err
}
return nodes, nil
}